Step 1: First law of Faraday.
The first law of Faraday of electrolysis states that:
"The amount of substance liberated at an electrode during electrolysis is directly proportional to the quantity of charge passed through the electrolyte."
Mathematically, it is expressed as:
\[
m = \frac{Q \cdot M}{F \cdot z}
\]
where:
- \( m \) is the mass of the substance liberated at the electrode,
- \( Q \) is the total charge passed (in coulombs),
- \( M \) is the molar mass of the substance,
- \( F \) is Faraday's constant (approximately 96500 C/mol),
- \( z \) is the valency of the ion.
Step 2: Conclusion.
This law relates the amount of substance deposited during electrolysis to the charge passed, which is fundamental to understanding electroplating and other electrochemical processes.